In Schneider, U.S. patent application Ser. No. 07/584,104--Automated Point-of-Sale Machine, herein referred to as the `Schneider '104 invention`, Schneider discloses a method and apparatus which allows consumers to check out their purchases with a minimal of direct human assistance. The Schneider '104 invention possesses significant improvements with respect to the prior art in the areas of customer fraud, shopping efficiency, non-coded products and use by non-experienced users. The Schneider '104 invention consists of two major modules--the self-service unit utilized by the customer, herein referred to as the `robot module` and the unit utilized by the store employee to supervise the operations of several robot modules, herein referred to as the `supervisor module`. The customer presents himself/herself at any available robot module with the items he/she has selected for purchase. The customer scans a product item and then places it into a bag resting on a scale, herein referred to as the `packing scale`. The electronic signals from the scanner and the scale go to an electronic computer which contains (or can access) a product lookup table allowing the increase of weight on the packing scale to be verified against product number. The customer repeats this operation for all remaining items. If a weight change does not correspond with the product number then the customer will receive an audio and/or visual prompt to this effect from the robot module. Prompts typically are simultaneously transmitted to the supervisor module. A bidirectional intercom system allows the supervisory employee to immediately help the customer with any difficulties and if necessary, via the supervisor module keyboard, directly enter commands or product information. When the customer has scanned and bagged all items selected for purchase, the customer goes to the supervisor module to pay, or if the robot module is so equipped, as it would typically be in the case of debit or credit cards, the customer remains at the robot module for payment. In either case, the customer is instructed to leave the bag on the packing scale alone. Removing the bag from the packing scale will cause a change in weight (or similarly, adding a nonscanned item to the bag will cause a change in weight) that will be noticed by the computer and cause warning to be given. Only after the computer receives a signal that payment has been received will it allow the bag from the packing scale to be removed without a warning prompt occurring. Note that the customer has handled each item only one time. The customer scans and then directly bags the item. The item nor the bag is not handled again until checkout is finished, thus allowing a high shopper efficiency. A small exception occurs if the customer has items too numerous to fit in the bag(s) on the packing scale in which case full bags are slid several inches to an adjacent larger `storage` or `bagging` scale where weight changes are monitored by the computer. Before the customer uses the robot module, he/she presses a button or switch indicating the level of experience he/she has with this type of automated point-of-sale machine. For `beginner` customers, when they have an item not containing a machine readable bar code, as indicated by pressing a `no bar code` button on the robot module, they will be instructed to place the item directly into the bag on the packing scale where its image is sent to the supervisor module. The supervisory employee receives a prompt to examine the image and to enter the product number or a corresponding abbreviation of the new item. In the case of the `experienced` customer, the computer monitor of the robot module will present the customer with a menu selection in order for the customer to qualitatively identify the product and optionally identify its quantity. After identification, typically involving pressing a button corresponding to a choice on a sub-menu, the customer is instructed to place the item in the bag on the packing scale. An image of the bag's new contents along with the customer's identification are presented to the supervisory employee via the supervisor module for verification. In the case of both the `beginner` and `experienced` customers, the weight change on the packing scale is evaluated by the computer with reference to the product number ultimately chosen to see if the weight change is reasonable. If the weight increase differs by more than the allowed tolerance for that product, then the supervisory employee will receive a prompt to inspect the transmitted video image with more care. Note that with only a small investment of the supervisory employee's time and with little confusion to the inexperienced user, that a product not bearing a machine readable code is accurately identified. In particular, note that the customer is not obligated to key in a series of product number digits to identify the product.
Although the Schneider '104 invention possesses many improvements with respect to the prior art, the present invention improves upon the Schneider '104 invention further. In the Schneider '104 invention it is occasionally difficult for the supervisory employee to distinguish produce items placed into the bag on the packing scale for identification among the other products already present in said bag. The present invention discloses a method and apparatus to increase both the speed and the accuracy of such identifications required of the supervisory employee. The existence of flat, non-active surfaces, in particular the surface adjacent to the scanner, where customers can leave non-scanned items for later fraudulent retrieval, gives customers the opportunity, albeit a small one, for theft. The present invention discloses a method and apparatus to eliminate even this small opportunity for theft. In the Schneider '104 invention the supervisory employee must spend a certain amount of time giving customers receipts and a certain amount of time taking coupons from customers. The present invention discloses a method and apparatus to reduce such time requirements of the supervisory employee. In the Schneider '104 invention each checkout station requires a set of video and camera monitors at the supervisor module. If the supervisory employee is to supervise 6 or 8 robot modules (i.e., checkout stations), then the supervisory employee would possibly have to view 16 monitors. The present invention discloses a method and apparatus whereby the supervisory employee need only supervise one set of typically two monitors.